The present invention relates to a coating mechanism for applying varnish in a leaf-type offset printing apparatus, and more particularly to a mechanicm for appyling a lustrous and uniform varnish coat to the printing surface.
In conventional varnish coating apparatus the layer of varnish on the roller surface becomes thinner after the varnish is applied to a blanket drum which, like the printing blanket drum, has two surfaces of print and non-print so that the varnish blanket drum is covered partially with varnish for the printed areas only. Usually aqueous varnish is used on printing surface to facilitate drying in an in-line method. As the amount of varnish on the roller surface is not maintained uniform, the lustrous surface on the printing cannot be produced precisely.